I was just on the phone with scooterworks for something and decided to ask a question about something I have often wondered. What does this do exactly? He didn't know and after asking around said he only got blank stares. I asked why they even sell it then, but again; no idea.
http://www.scooterworks.com/Coil_Feeding_-_VBB_etc__P980C87.cfm
This one's for all the the hardcore vintage guys, you know who you are.

Ok, I was looking at the _real_ magneto lnk on Wikipedia as well, and then noticed that the icon they use to denote "automotive related link" looks an awful lot like the Haynes 2 stroke spark plug picture.

No chance. I stored the VBB in my house over the winter and have been enjoying it all spring. I was recently hornswaggled into fixing a local guys Vespas and just came to the blank realization that I really had no concept of what that coil did. That VBB will remain as it is until it ceases to operate; at that time I may actually allow it to be in the same room as a wrench.